CONTROLLED SIMULTANEOUS DEACIDIFICATION AND ALCOHOL FERMENTATION OF AHIGH-ACID GRAPE MUST USING 2 IMMOBILIZED YEASTS, SCHIZOSACCHAROMYCES-POMBE AND SACCHAROMYCES-CEREVISIAE

Saccharomyces cerevisiae W3 and Schizosaccharomyces pombe IFO 0358 wer e separately immobilized in double-layer Ca-alginate fibers. White win es were made from a high-acid Ezerfurtu white must using the fiber-imm obilized yeasts in different combinations. The best results in terms o f wine quality, especially in acidity and lack of off-odors, were obta ined when immobilized Schizosaccharomyces pombe fibers were removed as soon as the malic acid in the fermenting must had decreased to a desi rable content, and then allowing the fermentation to proceed to comple tion by the addition of the immobilized Saccharomyces cerevisiae fiber s, The use of gel fibers with the two immobilized yeast strains permit ted easy and effective control of both deacidification and alcohol fer mentation. The white wine made by the method had only a small amount o f sediment, little distinct off-flavor, and less than 10(3) free yeast CFU/mL in the must at the end of the fermentation.